The present disclosure relates generally to vehicle transmissions, and particularly to a hybrid clamping mechanism for belt continuously variable transmission and method of use thereof.
Belt continuously variable transmissions (CVT's) transfer torque by means of the friction contacts between belt elements and pulley surfaces. A lack of a positive engagement, such as that found in a gear tooth arrangement for example, results in the application of substantial clamping forces being required at the belt element. To achieve variable clamping loads where required pressures may be controlled (modulated) as a function of input torque and speed ratio, hydraulic forces are employed. However, large clamp forces require a high capacity hydraulic pump, which consumes power and may negatively effect transmission efficiency and vehicle fuel economy. Accordingly, there is a need in the art for a belt CVT that overcomes these drawbacks.